Renee Salas, a physician at Massachusetts General Hospital, has been thinking about the connections between climate change and public health for a long time. In her emergency room in Boston, she sees the consequences of warming up close. Extreme heat, air pollution, vector-borne diseases, and longer allergy seasons are taking a toll on her patients. “My job as an emergency medicine doctor is to protect my patients and keep them healthy,” she said at a press briefing on Thursday. “Climate change increasingly threatens my ability to do that.”

Salas was at the briefing to weigh in on a new report that shows the health costs of climate change now far exceed $820 billion per year in the United States. One of her patients, she told reporters, a middle-aged man, visited her emergency department 30 times in one year with debilitating symptoms of Lyme disease—a tick-borne illness that can cause fever, headache, muscle pain, and neurological damage. She treated a four-year-old girl who had to seek emergency care for asthma attacks intensified by climate-driven pollen seasons and air pollution. The girl’s mother, a single parent, asked Salas for a doctor’s note so that she could show her boss that she was missing work for a legitimate reason—she had already been forced to miss three shifts that week and would likely have to miss more to care for her sick child.

“Receiving care for climate-sensitive diseases can quickly add up,” Salas, who was not involved in the making of the report, said. “We can no longer ignore these costs and they have to be factored into our decision-making.”

Read the full article about the health impacts of climate change by Zoya Teirstein at Grist.